# Medical emergency of Matthew Mayich

> Live situation record from CLSTR: https://clstr.news/situations/medical-emergency-of-matthew-mayich
> Updated: 2026-09-05T09:00:00.000Z. Sources: 30. Developments: 4.

On August 20, 21-year-old Matthew Mayich, a defenseman and St. Louis Blues prospect at Arizona State University, collapsed during an outdoor workout in Tempe. While initial reports suggested heat-related illness, subsequent updates indicated Mayich suffered cardiac arrest and exertional heatstroke during a military-style training session.

As of early September, Mayich remains hospitalized. His attorney, Robert Carey, has provided conflicting descriptions of his medical state; while previously reported to be in a coma, Carey stated on September 3 that describing his state as a coma is ‘no longer accurate,’ alleging the athlete’s body has ‘fundamentally ceased to function’ and his condition is irreversible. However, other reports from September 5 suggest he remains in a coma.

Carey has criticized the 60-minute conditioning session as ‘grueling’ and ‘onerous,’ noting it involved high-intensity drills with minimal rest and only one water break. The family is demanding an independent investigation, alleging that Arizona State University may have violated its own heat policy. Specifically, Carey claims Mayich had been in the Phoenix area for only five days, which would have bypassed the required one-week acclimatization period. Further allegations suggest safety protocols were ignored, including a lack of immediate cooling measures like an ice bath or cold water immersion following the collapse.

New details indicate the session was reportedly led by Tim Ziesel, a former Green Beret working as an external contractor, rather than a hockey coach. Arizona State University has launched a review of the incident. Athletic director Graham Rossini stated the university is ‘reviewing the facts and understanding the scenario,’ noting that coaches and trainers were present during the session.

## Timeline

### 2026-09-05: Matthew Mayich hospitalized after collapse during Arizona State training

Hockey player Matthew Mayich is hospitalized after collapsing during an Arizona State University training session. His family is demanding an investigation into potential heat policy violations.

3 sources. https://clstr.news/cluster/matthew-mayich-family-demands-investigation-after-players-heatstroke-collapse

### 2026-09-03: Arizona State hockey player Matthew Mayich in critical condition after workout collapse

Arizona State hockey player Matthew Mayich remains in critical, irreversible condition after collapsing during a hot outdoor workout on August 20. His family's attorney is seeking an independent investigation.

6 sources. https://clstr.news/cluster/arizona-state-hockey-player-matthew-mayich-in-critical-condition-after-workout-collapse

### 2026-08-31: Matthew Mayich remains in coma after ASU workout collapse

NHL prospect Matthew Mayich is in a coma with “zero chance of recovery” after collapsing during a high-intensity outdoor workout in extreme heat at Arizona State University.

12 sources. https://clstr.news/cluster/matthew-mayich-remains-in-coma-after-outdoor-workout-collapse

### 2026-08-26: Matthew Mayich hospitalized after Arizona State workout collapse

St. Louis Blues prospect Matthew Mayich remains hospitalized after collapsing during an outdoor workout at Arizona State University amid extreme heat in Tempe.

11 sources. https://clstr.news/cluster/arizona-state-hockey-player-matthew-mayich-hospitalized-after-collapse

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Cite as: Medical emergency of Matthew Mayich. CLSTR, https://clstr.news/situations/medical-emergency-of-matthew-mayich